class User < ApplicationRecord
  has_many :microposts, dependent: :destroy
  has_many :active_relationships, class_name: "Relationship",
           foreign_key: "follower_id",
           dependent: :destroy
  has_many :passive_relationships, class_name: "Relationship",
           foreign_key: "followed_id",
           dependent: :destroy
  has_many :following, through: :active_relationships, source: :followed
  has_many :followers, through: :passive_relationships, source: :follower
  attr_accessor :remember_token, :activation_token, :reset_token
  before_save :downcase_email
  before_create :create_activation_digest
  validates :name, presence: true, length: {maximum: 50}
  VALID_EMAIL_REGEX = /\A[\w+\-.]+@[a-z\d\-.]+\.[a-z]+\z/i
  validates :email, presence: true, length: {maximum: 255},
            format: {with: VALID_EMAIL_REGEX},
            uniqueness: {case_sensitive: false}
  has_secure_password
  validates :password, presence: true, length: {minimum: 6}, allow_nil: true

  scope :admin, -> {where admin: true}

  def User.digest(string)
    cost = ActiveModel::SecurePassword.min_cost ? BCrypt::Engine::MIN_COST :
        BCrypt::Engine.cost
    BCrypt::Password.create(string, cost: cost)
  end

  def self.new_token
    SecureRandom.urlsafe_base64
  end

  def profile_url
    "users/#{id}"
  end

  def remember
    self.remember_token = User.new_token
    update_attribute(:remember_digest, User.digest(remember_token))
  end

  def authenticated?(attribute, token)
    digest = send("#{attribute}_digest")
    return false if digest.nil?
    BCrypt::Password.new(digest).is_password?(token)
  end

  def forget
    update_attribute(:remember_digest, nil)
  end

  def activate
    update_attribute(:activated, true)
    update_attribute(:activated_at, Time.zone.now)
  end

  def send_activation_email
    UserMailer.account_activation(self).deliver_now
  end

  def create_reset_digest
    self.reset_token = User.new_token
    update_attribute(:reset_digest, User.digest(reset_token))
    update_attribute(:reset_sent_at, Time.zone.now)
  end

  def send_password_reset_email
    UserMailer.password_reset(self).deliver_now
  end

  def password_reset_expired?
    reset_sent_at < 2.hours.ago
  end

  def feed
    following_ids = "SELECT followed_id FROM relationships
                     WHERE  follower_id = :user_id"
    Micropost.where("user_id IN (#{following_ids})
                     OR user_id = :user_id", user_id: id)
  end

  def follow(other_user)
    following << other_user
  end

  def unfollow(other_user)
    following.delete(other_user)
  end

  def following?(other_user)
    following.include?(other_user)
  end

  private

  def downcase_email
    self.email = email.downcase
  end

  def create_activation_digest
    self.activation_token = User.new_token
    self.activation_digest = User.digest(activation_token)
  end
end

